1. Field of the Invention
The present invention relates to security systems. More specifically, the present invention relates to cordless security systems employing a wireless telephony resource in conjunction with a local cordless protocol for communication with plural security sensors, alarms, and control stations.
2. Description of the Related Art
Residential and commercial security systems are known in the art. Such systems generally include several sensors that detect various stimuli and produce sensor signals as a result of such detection. Conductive loop sensors are used to detect door and window opening stimuli. Smoke and carbon monoxide detectors sense their corresponding atmospheric conditions. There are also motion detectors, glass breakage detectors, and other detectors known to those skilled in the art. Security systems generally include a control panel that enables user access for programming, operation, password entry, alarm cancellation and so forth. When a sensor signal is received, it is coupled to the control panel, which will perform some action in response to receipt of the signal. Frequently, an alarm signal is sent to an alarm, such as a siren, horn, or bell, which activates that alarm. Another possible response is for the control panel to access a remote location and report the alarm condition. The remote may be an alarm monitoring company or an individual interested in receiving notice of an alarm condition.
Alarm systems have traditionally used electric wires or cables to interconnect the various sensors with the control panel. Sometimes remote keypads are included to allow user access, for example, at entry points to the protected home or facility. Telephone service has been used to access the remote locations. Such service has traditionally been connected with a metallic telephone circuit from the user's facility to the public switched telephone network (“PSTN”). Of course, there are disadvantages to using wires to interconnect security systems. Installation cost is high, the wires are prone to damage over time, and the wires may be intentionally cut in an effort to disable the security system. Others have addressed the disadvantages of wire-connected security systems be employing various wireless devices.
U.S. Pat. No. 5,200,735 to Hines for WEATHER PROTECTED PORTABLE SECURITY SYSTEM FOR IN-FIELD USE discloses a wireless security system with several types of remote sensors, each having a transmitter for sending a signal to a master control to report a sensed condition. The master control includes a receiver for receiving the sensor transmissions, and a transmitter for sending a signal to a remote alarm unit in response to a sensed condition. The master control unit can activate a remote audible alarm and dial a telephone number through a cellular telephone, which is directly coupled to the master controller.
U.S. Pat. No. 5,587,701 to Hess for PORTABLE ALARM SYSTEM (“Hess(1)”)discloses a portable alarm system with most of the alarm functions contained in a portable enclosure. Some of the sensors are included in the enclosure and some communicate via radio signals. The alarm is capable of initiating a telephone call to a security monitor station either by conventional hard-wired telephone lines within a building or through a cellular transceiver that is directly coupled to the portable enclosure.
U.S. Pat. No. 6,049,273 to Hess for CORDLESS REMOTE ALARM TRANSMISSION APPARATUS (“Hess(2)”)is a continuation-in-part of Hess(1). Hess(2) adds the concept of a “cellemetry” modem, which is a method of communicating over the cellular network using cellular data instead of voice. Hess(2) also teaches the use of a cordless transmitter to allow the device to access dial tone through a nearby cordless telephone transceiver to access a landline telephone resource.
U.S. Pat. No. 6,255,944 to Addy for REMOTE INDICATION DEVICE FOR USE IN WIRELESS SECURITY SYSTEMS discloses a wireless security system with a central control unit and a remote indication device. The central controller is coupled to a wireless telephone dialer. The remote indication device provides feedback in the form of a display indicating commands and status of the system. Alarm conditions are first transmitted to the central receiver, then forwarded by radio to the remote indication device, finally, the remote indication device sends them back to the central receiver, where a suitable alarm is activated.
The prior art does address the use of wireless technology to overcome the problem with wired security systems. The use of a cellular telephone eliminates the risk of the telephone lines from being cut, but does so at the added cost of employing a dedicated cellular telephone resource. A cordless telephone interconnection is taught, however, the cordless base unit must be tied to a metallic loop, which is vulnerable to damage or sabotage.
It is therefore understood that wireless security systems are known, however each has some disadvantages as to cost or resource utilization. Especially considering the general need users have for telephony services at most facilities that are protected by a security system. Thus, there is a need in the art for a wireless security system and method that overcomes the problems in the prior art, and which integrates resources to maximize utilization while still overcoming the problems associated with wired security systems.